Rhodeus smithii is a temperate freshwater fish belonging to the Acheilognathinae subfamily of the Cyprinidae family. It originates in stagnant waters in inland rivers in Japan. It was originally described as Achilognathus smithii by Charles Tate Regan in 1908, and is also referred to as Rhodeus ocellatus smithii in scientific literature. It is listed as critically endangered in the IUCN Red List.